Remove transparency from d3heatmap

Question

I realized a heatmap using d3heatmap function but I get transparent color. How can I remove this transparency?

Moreover, as you can see I have a huge number of rows and the label were overlapped. Is there a way to format the label ? It's fine also if only some labels will be shown.

my code:

library("d3heatmap")

d3heatmap(b, col = coul, k_row =4, k_col = 4,show_grid = TRUE, key=TRUE)